1. Field of the Invention
The present invention relates to an electrical contact, and more particularly to an electrical connector contact for electrical interconnecting two electrical interfaces such as contact pads of an integrated circuit (IC) package and a printed circuit board (PCB).
2. Description of the Prior Art
There are two current trends in the connector industry that pose great challenges for manufacturers: the trend toward miniaturization of socket connectors, and the trend toward increased density of arrays of electrical contacts in the socket connectors. In a typical miniaturized socket connector, each contact received in a housing of the socket connector is short and occupies only a limited space. Thus a spring arm of the contact may be too short to provide good resilient characteristics. Consequently, engagement between the contacts of the socket connector and an associated electrical device may be unreliable.
In order to overcome the above problems, Taiwan Patent Issue No. 444960 discloses a socket connector. Referring to FIGS. 6, 7 and 8, the connector comprises a base 8 defining a plurality of passageways 80 arranged in a rectangular array having several rows and columns, and a corresponding number of contacts 9 received in the passageways 80. Each contact 9 defines a long elastic arm 92 and an engaging portion 91. Each passageway 80 includes two aligned slots 82 for engagingly receiving the engaging portion 91 of a corresponding contact 9. The slots 82 of diagonally adjacent passageways 80 are all aligned with each other, and cooperatively define a line oriented at an acute angle relative to the rows and columns of the array. The acute angle is typically 45 degrees. When the contacts 9 are received in the passageways 80, the arms 92 of the contacts 9 are each oriented at an angle of 45 degrees relative to the rows and columns of the array. This configuration enables each passageway 80 to be relatively long, thereby providing sufficient space to receive the long elastic arm 92 of the corresponding contact 9.
However, in assembly, a line of the contacts 9 is simultaneously inserted into a corresponding line of diagonally adjacent passageways 80, with the contacts 9 being detachably joined together by a common carrier strip in order to effect such simultaneous insertion. This procedure is repeated for each line of diagonally adjacent passageways 80. That is, firstly one contact 9 is inserted in a corner passageway 80 of the base 8 from a first carrier strip. Secondly, two contacts 9 are inserted in two diagonally adjacent passageways 80 from a second carrier strip. Thirdly, three contacts 9 are inserted three diagonally adjacent passageways 80 from a third carrier strip, and so on. The first, second, third and other carrier strips all have different lengths, and carry different numbers of the contacts 9. This makes manufacturing of the carrier strips unduly complicated, and also makes the procedure for inserting the contacts 9 unduly complicated.
FIG. 9 shows a conventional contact 60 comprising a retention portion 61, a soldering portion 64 bent perpendicularly from one end of the retention portion 61, and an engaging portion 63 extending from an opposite end of the retention portion 61. The engaging portion 63 has a curved configuration substantially perpendicular to the soldering portion 64. Thus the engaging portion 63 is relatively long, and gives the contact 60 good resilient characteristics.
Referring to FIG. 10, a corresponding contact strip 70 for the contacts 60 comprises an elongate carrier strip 66, a plurality of strip contacts 60′, and a plurality of connecting portions 65 interconnecting the strip contacts 60′ with the carrier strip 66. An engaging portion 63′ of each strip contact 60′ is relatively long, with the engaging portions 63′ of the strip contacts 60′ being aligned parallel to a longitudinal axis of the contact strip 70. Thus gaps between adjacent strip contacts 60′ are relatively large. When the contact strip 70 is formed from sheet metal, there is considerable wastage of material, which increases manufacturing costs.
An improved electrical contact that overcomes the above problems is desired. A copending application with a Ser. No. 10/166,890, now U.S. Pat. No. 6,652,329 having the same assignee with the instant application, discloses some approach.